Background: Respiration is considered to be one of the most significant physiological processes. In order to prepare patients to recognise the type of prosthesis they need, a prosthodontist should focus on developing a complete understanding of the patient. As a result, the current study was carried out to evaluate the impact of complete dentures on pulmonary function. Materials and Methods: 100 patients who had a complete edentulous arch and a history of wearing complete dentures for at least five years were included in the study. Trained technicians carried out each and every spirometric operation. The spirometric test was carried out using a diagnostic spirometer.The following procedures were followed during testing: Stage 1 involves testing without a denture, Stage 2 involves testing with both dentures present, Stage 3 involves testing with a maxillary denture only, and Stage 4 involves testing with a mandibular denture only.The results of the spirometric test were recorded as forced vital capacity (FVC), peak expiratory flow (PEF), forced expiratory volume in one second (FEV1), and forced expiratory flow 25%–75% (FEF25–75).SPSS software was used to analyse every outcome. Results: The spirometric value of FVC, PEF, FEV1, and FEF25–75 in the absence of both maxillary and mandibular dentures was found to be 4.23, 6.21, 3.64, and 1.89, respectively. The spirometric value of FVC, PEF, FEV1, and FEF25–75 in the presence of both maxillary and mandibular dentures was found to be 3.63, 4.95, 2.08, and 1.99, respectively. While analyzing statistically, it was seen that there was a significant decrease in the value of spirometric variables in the presence of dentures. Conclusion: According to the aforementioned findings, prolonged denture wearer edentulous patients are at risk of developing spirometric changes. Therefore, prompt advice on the various respiratory exercise regimes should be given to these patients. Keywords: Complete denture, spirometry, Forced vital capacity